...
- The entity attribute is found in
md:EntityDescriptor/md:Extensions/mdattr:EntityAttributes. We recognise that the Entity Attributes specification allowsmd:EntitiesDescriptor/md:Extensions/md:EntityAttributeselements, but we rule them out for operational and conceptual reasons. - There is only one instance of an Entity Selection Profile entity attribute in an entity. Behaviour when more than one is present is not defined by this profile.
- Composition with other sources of filtering is not defined by this profile
- The value of the entity attribute is Base64 encoded [Base64]
- Syntax of the decoded value is defined by the metadata consumer.
- Any whitespace before, after or internal to the value must be ignored
...
- The expected consumer of the entity attribute is a discovery service. Federation operators and entity operators are not expected to decode the value.
- Syntax and semantics Semantics of the decoded value are defined by the metadata consumer.
- We recommend that null values, incorrectly encoded values or other errors are treated as if there was no filtering. We do not recommend that the whole entity metadata is considered invalid.
- If the decoded value does not conform to the requirements of the consumer, we recommend that the consumer assumes there is no filtering. We do not recommend that the entity metadata is considered invalid.
...